Yarn tensioning device



March 7, 1967 P. VERBEEK YARN TENSIONING DEVICE Filed May 10, P965 FIG. 2

I NVEN TOR.

PETRUS VERBEEK Patented Mar. 7, 1967 3,307,805 YARN TENSIONING DEVICE Petrus Verbeek, Steenbergen, Netherlands, assignon to American Enka Corporation, Enka, N.C., a corporation of Delaware Filed May 10, 1965, Ser. No. 454,589 Claims priority, application Netherlands, May 16, 1964, 64/05516 8 Claims. (Cl. 242- 129.8)

This invention relates to a device to be used in conjunction with yarn packages when thread is to be withdrawn from the package for further processing.

When twisted yarn is to be withdrawn from yarn packages to be fed into textile processing machinery the yarn packages are generally supported in a carrier or creel type device. Such a support device, which may hold any number of yarn packages, is used in warping operations. During warping operations, thread ends from a plurality of yarn packages supported on a creel are drawn over the ends of the packages, paralleled, passed through a series of thread guides, and fed in a flat sheet-like formation to a rotating beam. These beams, containing a plurality of thread ends, are used to supply thread to textile operations such as weaving, knitting, etc. where it is desired to have a warp of threads for processing. In circular knitting operations, yarn packages are also supported in such a way as to supply twisted yarn over the end of the package.

In both knitting and warping operations, the withdrawal of the twisted yarn threads from the individual package is generally intermittent, with repeated stopping and starting of the yarn withdrawal occurring throughout the normal processing cycle. When withdrawal of the twisted yarn is intermittent, there is a pronounced tendency of the yarn to overrun on the yarn package. When the withdrawal of yarn is suddenly interrupted, its rotational enertia causes a considerable amount of yarn to continue to leave the package. This override leads to entanglement of the thread end being delivered by a package and the formation of snarls in the yarn, which is in a relaxed state. Since the thread relaxes even back into the windings on the yarn package, snarls develop on the package itself. When withdrawal of the yarn is restarted, these snarls are often not drawn out of the yarn and cause thread breakage at the thread guides. If the snarled yarn passes on to a warp beam or into a knitting machine, these snarls are incorporated into subsequent fabric as imperfections.

Another irregularity in withdrawal of yarn from the end of a stationary yarn package occurs because of the ballooning effect of the yarn as the yarn package decreases in diameter during thread withdrawal. This ballooning effect produces variation in tension in the yarn passing to a warper beam or knitting machine. These variations also produce imperfections in subsequently fabricated products.

To overcome these problems in end-wise withdrawal of thread from yarn packages, various devices are known which produce tension on the yarn as it leaves the yarn package. Specifically, apparatus has been designed which peripherally encloses a yarn package to exercise a constrictive pressure on the periphery of the wound yarn. Generally, the enclosing device will continuously engage a portion of the peripheral surface of the package and press on the outer surface of the yarn to prevent thread overto hang freely-over the package and contact opposite sides of the package. However, the fabric contacts only a small portion of peripheral surface of the yarn package and, as the diameter of the yarn package decreases during removal of the thread, this contact surface becomes even smaller. Because such a small area is contacted, interru-ptions in withdrawal of the yarn still create snarls or entanglements in the threads. Also balloon tension variations caused by the decrease in the package diameter cannot be effectively reduced.

Because the peripheral contact area diminishes as the package is unwound, thread withdrawing tension will vary throughout the operation. This adds to nonuniformity in the fabricated product. Another disadvantage of the above mentioned apparatus is that it requires much more space for the free ends of the retarding fabric which elongate as the package becomes thinner. In a warping creel, which supports many yarn packages, this space is generally not available.

Another type yarn tensioning means is disclosed in U.S. Patent 2,869,802. The device consists of a plurality of strips or blades of flexible material which are biased against the peripheral surface of the yarn package and contact this surface at point intervals about the circumference to produce a tension on the yarn as it is withdrawn from the package. However, since the flexible strips are fixed in package-contacting position at the beginning of the unwinding of the package, the tension exerted on the thread being withdrawn from the package varies as the package diameter decreases. Any attempt to produce a uniform tension in the yarn throughout the unwinding cycle must necessarily be accomplished by repeated adjustment of the individual positions of each strip. This adjustment, of course, is completely impractical in a continuous thread removal operation.

Still another means for controlling yarn tension is disclosed in U.S. Patent 2,909,913. In this patent the inherent wildness of stretch type yarns is controlled by applying to a portion of the outer surface of the yarn supply package a knitted tube. The tube is made from a knitted fabric and is designed to contact the yarn package at only one circumferential point along the length of the package. The pressure exerted by the tube on the package at this point is manually adjusted prior to the start of yarn takeup. This apparatus also produces variable tension in the thread being removed from the package as the package decreases in diameter. Also, because the tube contacts the yarn periphery at only one point along the axis of the package, there is no way to prevent the thread being withdrawn from becoming tangled as it slides, in a some what relaxed condition, along the surface of the yarn package.

A major disadvantage in all of the mentioned devices used to prevent tangling or snarling of twisted yarn during intermittent operations is the fact that they cannot be used with textile devices which require a continuous supply thread from each yarn supply point. In warping operations and in knitting operations which produce a product requiring more than one yarn package, it is necessary that the multi-package, transfer tail system be used. In this arrangement, at least two yarn packages are located adjacent each thread supply point, the trailing edge of the leading thread supply package being attached to the leading edge of the second yarn package. As the yarn on the leading thread package is depleted, it automatically shifts the thread supply, via the transfer tail, to the second package. As the second package supplies thread to the system, the empty spool of the first package is replaced with a fresh thread package and its leading thread attached to the transfer tail of the second package, In this way, a continuous thread can be supplied from each thread point without shutting down operations to replace individual thread packages. The thread tensioning apparatus known heretofore are not adapted to this plural package set up. Their use in a continuous supply system would necessitate stopping the overall operation to replace individual empty yarn packages. This of course is completely impractical in large thread supplying operations such as warping.

It is an object of the present invention to provide an apparatus for maintaining tension in twist-lively thread during supply from yarn packages which overcomes the disadvantages of the prior art.

It is a primary object of the present invention to provide an improved apparatus for preventing the formation of snarls and tangles during withdrawal of twisted yarns.

It is another object of this invention to provide a uniform tension to thread being withdrawn from a yarn package throughout the entire period necessary to deplete the package.

It is still another object of this invention to provide a yarn tensioning means for maintaining a constant and uniform tension on twisted thread packages when employed to supply thread to apparatus requiring an uninterrupted thread supply source, i.e. supply systems requiring transfer tail tie-in.

The objects of the present invention are accomplished by employing, as a yarn package tensioning means, a device comprising a retarding strip of fabric which surrounds the yarn package, extends over the entire surface length of the package, and contacts the peripheral yarn of the package throughout an angle of at least 270 during the entire period of yarn Withdrawal from the package. The area of contact of the fabric with the peripheral surface of the yarn package is maintained constant, and remains so, independent of the outside diameter of the package which decreases as the yarn is withdrawn. When use is made of the apparatus of this invention, the formation of snarls and entanglement of yarns may be prevented under all conditions, and variations in balloon tension which occur during decrease in package diameter are reduced to a minimum. The tension on the thread supplied from the yarn package is maintained constant throughout the supply period, thus eliminating the undesirable variations heretofore thought unavoidable in the prior art.

A preferred embodiment of the invention consists of a retarding strip of fabric. One end of the fabric is attached to a fixed fastening bracket which is spaced from a horizontally supported yarn package and extends parallel to the longitudinal axis of the package. The bracket and fabric strip extend over the entire length of the yarn package. The fabric retarding strip extends from the fastening bracket around the yarn package in the direction of rotation of the thread being unwound from the stationary package. The retarding strip is maintained in contact with the peripheral surface of the yarn package through an angle of at least 270. The thread being withdrawn from the package rotates about the package and entrains the retarding strip in such a way that, even during a package diameter reduction, the retarding strip is kept in contact with periphery of the package to exert the desired pressure on the package and the required tension on the thread being withdrawn. The apparatus is constructed so that the surplus portion of the retarding strip, which accumulates as the package diameter decreases, is collected between the fixed fastening bracket and the periphery of the package. In this way, it is possible to have a large number of packages positioned in close arrangement, as in a creel.

In order to further illustrate the present invention, and to point out the unique features which enable it to eliminate the disadvantages of the prior art, reference may be made to the accompanying diagrammatic drawings and detailed explanation.

FEGURE l is a perspective view of the apparatus according to the invention showing a full yarn package prior to initial yarn withdrawal.

FIGURE 2 is a view which shows two horizontally sup- 4- ported yarn packages employing the unique apparatus of this invention during a yarn supplying operation.

FIGURE 3 is a view which shaws the apparatus of the present invention mounted on a yarn package support means with the retarding strip opened for better illustration of the individual parts of the invention.

FIGURE 4 is a view which shows, on a larger scale, a schematic presentation of a horizontal slit which is utilized to enable plural supply packages to be attached by means of a transfer tail.

In FIGURE 1 is shown a full yarn package 1 which is placed on a supporting peg 3 attached substantially horizontally to a framework or creel support means 2. The framework 2 forms part of a generally known warping creel (not shown). The creel contains a large number of yarn packages from which yarn,is unwound over the ends thereof while the packages are maintained stationary. The thread ends from the individual yarn supply positions are fed through a series of thread guides to a warping beam where they are collected in a sheet of parallel threads. Attached to the support peg 3 is a fixed fastening bracket 4 to which is attached one end 5 of a fabric retarding strip 6. The particular material used in the fabrication of the strip may vary. The present invention utilizes a fused nylon fabric to form the retarding strip.

The retarding strip extends about and encompasses the yarn package 1. Bracket 4 is provided with pins 7 and the trailing end 9 of the retarding strip is provided with holes 8 which cooperate to attach the trailing end of the strip to the fixed bracket 4. The width of the retarding strip 6 is slightly greater than the actual length of the yarn package 1.

The retarding strip extends about the package through an angle of 360, and is in contact with the package over approximately the same distance. The length of the retarding strip is somewhat greater than the circumference of the full package. The excess length of the strip, referred to in FIGURE 2 by numeral 13, is collected as it accumulates during thread withdrawal from the yarn package in the space between the fastening bracket 4 and the outer surface of the package. The retarding strip 6 extends from the fastening bracket in the direction of rotation of the thread 11 being unwound from the stationary package 1. The thread is fed by way of thread guide 12 to a warper beam or knitting machine (not shown).

If more weight is needed in the retarding strip, the strip 6 may be provided with a plurality of sewn pleats 13 into which pieces of metal may be inserted.

At an angular distance from the fastening bracket 4, which is approximately in the case of the fullpackage shown in FIGURE 1, one end of a tensioning strip 14 is sewn to the retarding strip 6. The tensioning strip also extends in the direction of rotation of the yarn and is attached to a tensioning bracket 16, which is biased in the same direction by a weight 15 rotatably afiixed about the support peg 3 and connected to the tensioning bracket 16. The tensioning strip 14 may be made of the same fabric as that of the retarding strip 6.

As thread 11 is withdrawn from the yarn package, the diameter of the package gradually decreases. The effect of this decrease on the apparatus of the invention can best be seen in the right hand package of FIGURE 2. The retarding strip 6 remains in contact with the package at an angular distance of approximately 360 due to the pressure exerted by the tensioning strip 14 and the weighted pleats 13. Additionally, the rotary motion of the thread 11, as it is pulled from the fixed yarn package, tends to entrain the retarding strip. As the diameter of the package decreases, the end of the retarding strip which is attached to the fixed bracket 4 by means of pins 7 and holes 8 accumulates in the space between the peripheral surface of the package and the bracket 4. This accumulation is collected in the form of pleats 10.

As the package diameter decreases, weight swings downward-from its approximately horizontal initial position, thus raising tensioning bracket 16, which in turn maintains a uniform pressure of the retarding strip on the surface of the yarn package by means of tensioning strip 14. When the package is exhausted, the weight 15 will be in approximately a vertical position and no longer exert any appreciable force on the tensioning strip. The operation of'weight 15 insures that during the entire unwinding process, the yarn package and the thread unwound therefrom are subjected to the desired pressure independent of the outside diameter of the package.

FIGURE 2 shows a warping creel thread supply position composed of two horizontally supported yarn packages 18 and 19. The supply point serviced by these two packages feeds a single thread to the warping beam. The thread shown being supplied is unwound from package 18, and package 19 serves as a reserve package for the supply of thread after package 18 is exhausted. To insure that the fresh package 19 takes over the unwinding process without interruption, yarn package 18 is provided with a transfer tail 20 which is tied to the initial .thread length 21 of the package 19. Package 19 is in turn provided with a transfer tail which, after the empty bobbin 17 of package 18 has been removed, is tied to the initial thread length of a full package to be mounted on the empty peg. v

To provide for the passage of the transfer tail during changeover from the empty bobbin to the auxiliary supply bobbin, each retarding strip 6 is provided with a longitudinal slit 22. The retarding strip 6 is held together at the slit 22 by the provision of a U-shaped, hairpin-like resilient member 25. The U-shaped member is inserted into two hems sewn into the retarding strip adjacent the slit 22. When member is in position, the slit is unrestricted throughout the width of the retarding strip 6 and allows passage of the transfer tail during yarn package changeover. Because of the open end 23 of the U-shaped member, the transfer tail, which has been aligned with the strip prior to initial start-up of the warping operation, is allowed to pass free of the retarding strip 6 during the thread transfer. In order to have the transfer tail project from the retarding strip at a convenient point, the slit 22 may be closed over about one-fourth of its length, which distance is indicated by numeral 26.

In order to better show the individual parts of the present invention, FIGURE 3 illustrates a thread support position from which a yarn package has been removed and the retarding strip device opened up. In this view of the apparatus, a better view of the relationship of the individual parts can be seen.

In FIGURE 4 is illustrated, on a larger scale, a schematic diagram of the construction of the retarding strip 6 at the transfer tail slit 22. The U-shaped member 25 is shown inserted into the pleats formed adjacent the slit. The inside of the retarding strip 6 adjacent the slit 22 may be provided with a closing strip 27 which shuts off the slit 22 from the surface of the yarn package 1. The closing strip 27 may also be covered with fur, as shown at 28, to prevent abrasion of the yarn during its removal from the yarn supporting pirn.

It is apparent that many changes and modifications may be made in the apparatus described without departing from the spirit of the invention. It is therefore understood that the particular construction of the apparatus described above is not intended to be limitative on the invention and the scope of the invention is intended to be limited only to the extent of the following claims.

What is claimed:

1. An apparatus for preventing snarls and tangles in a twisted yarn during end-wise removal of the yarn from a substantially cylindrical yarn package supported by a yarn support means, said apparatus being attached to said yarn support means and comprising substantially a horizontal peg attached at its base to said yarn package support means and having a free end to receive a yarn package thereon, a fixed fastening bracket attached to the base of the horizontal peg and having an arm extending the length of the yarn package and being spaced from the outer periphery thereof, a fabric retarding strip having one end attached to and extending the length of said arm, said retarding strip completely encircling the outer periphery of a full yarn package and extending from said fastening bracket arm in the same direction as the rotation of yarn thread during removal from said yarn package, the other end of said retarding strip being removably attached to said fastening bracket arm, a tensioning strip having one end secured to said retarding strip intermediate the ends thereof, the other end of said tensioning strip secured to the arm of a weighted tensioning bracket, said tensioning bracket being rotatably affixed to the base of said peg,.a weight on said tensioning bracket positioned to exert a force on said retarding strip to maintain said retarding strip in contact with the peripheral surface of said yarn package at all times during yarn removal therefrom, a slit located in said retarding strip extending substantially parallel to the axis of said yarn package and completely across said retarding strip, a U-shaped fastening pin for securing the ends of said retarding strip on each side of said slit, the closed end of said U-shaped pin being located adjacent the base of said peg, a closing strip of material secured along one edge to the inner face of said retarding strip and located coextensive with said slit, the other edge of said closing strip overlying said slit to shut off communication of said slit with the surface of said yarn package, and a plurality of weights secured at circumferential intervals to the outer face of said retarding strip.

2. Apparatus as defined in claim 1 in which the force exerted by the weight on said tensioning bracket decreases in proportion to the decrease in diameter of said yarn package during yarn removal therefrom.

3. Apparatus as defined in claim 1 in which the tensioning strip extends for an angular distance of approximately around said yarn package when said yarn package is full of yarn.

4. Apparatus as defined in claim 1 in which said slit is sealed shut from the side of said retarding strip adjacent the base of said support peg for a distance approximately one-fourth the total length of said slit.

5. Apparatus as defined in claim 1 in which the side of the closing strip adjacent the yarn package periphery is covered with fur.

6. An apparatus for preventing entanglement of twisted yarn during end-wise removal of the yarn from a fixed, substantially cylindrical yarn package which consists of yarn retarding means surrounding the circumferential surface of the yarn package, said means being contiguous with at least three-fourths of said surface at all times during yarn removal, said yarn retarding means contacting substantially the same percentage of surface area of the yarn package throughout the period of removal of yarn therefrom, said yarn retarding means being composed of a strip of fabric having a width at least as great as the axial length of said cylindrical yarn package and having a length at least as great as the circumference of said package when it is full of yarn, fastening means for circumferentially positioning said strip of fabric with respect to said yarn package, and tensioning means for maintaining said strip in contact with the circumferential surface of said yarn package, said tensioning means consisting of a length of material secured at one end to said strip intermediate the length of said strip, the other end of said material secured to a biasing means rotatable about the axis of said yarn package, said biasing means exerting a force in a direction such that, as the diameter of the yarn package decreases during yarn removal, said strip of fabric is continuously urged into engagement with the circumferential surface of the yarn package.

7 8 7. Apparatus as defined in claim 6 in which the inner supply of yarn can be maintained upon exhaustion of said surface of said strip adjacent said fastening means and yarn package. the opposing circumferential surface of the yarn form a material receiving area for collecting circumferential eX- References Cited y the Examine! cess of said strip caused by decrease in the yarn package 5 FOREIGN PATENTS diameter during yarn removal.

8. Apparatus as defined in claim 6 in which thread 1110436 2/1956 France passage means is located in said strip of fabric to allow FRANK J COHEN Primary Examiner the last portion of the yarn in said yarn package to be attached to another yarn package whereby a continuing 10 LEONARD CHRISTIAN, Examlner- 

1. AN APPARATUS FOR PREVENTING SNARLS AND TANGLES IN A TWISTED YARN DURING END-WISE REMOVAL OF THE YARN FROM A SUBSTANTIALLY CYLINDRICAL YARN PACKAGE SUPPORTED BY A YARN SUPPORT MEANS, SAID APPARATUS BEING ATTACHED TO SAID YARN SUPPORT MEANS AND COMPRISING SUBSTANTIALLY A HORIZONTAL PEG ATTACHED AT ITS BASE TO SAID YARN PACKAGE SUPPORT MEANS AND HAVING A FREE END TO RECEIVE A YARN PACKAGE THEREON, A FIXED FASTENING BRACKET ATTACHED TO THE BASE OF THE HORIZONTAL PEG AND HAVING AN ARM EXTENDING THE LENGTH OF THE YARN PACKAGE AND BEING SPACED FROM THE OUTER PERIPHERY THEREOF, A FABRIC RETARDING STRIP HAVING ONE END ATTACHED TO AND EXTENDING THE LENGTH OF SAID ARM, SAID RETARDING STRIP COMPLETELY ENCIRCLING THE OUTER PERIPHERY OF A FULL YARN PACKAGE AND EXTENDING FROM SAID FASTENING BRACKET ARM IN THE SAME DIRECTION AS THE ROTATION OF YARN THREAD DURING REMOVAL FROM SAID YARN PACKAGE, THE OTHER END OF SAID RETARDING STRIP BEING REMOVABLY ATTACHED TO SAID FASTENING BRACKET ARM, A TENSIONING STRIP HAVING ONE END SECURED TO SAID RETARDING STRIP INTERMEDIATE THE ENDS THEREOF, THE OTHER END OF SAID TENSIONING STRIP SECURED TO THE ARM OF A WEIGHTED TENSIONING BRACKET, SAID TENSIONING BRACKET BEING ROTATABLY AFFIXED TO THE BASE OF SAID PEG, A WEIGHT ON SAID TENSIONING BRACKET POSITIONED TO EXERT A FORCE ON SAID RETARDING STRIP TO MAINTAIN SAID RETARDING STRIP IN CONTACT WITH THE PERIPHERAL SURFACE OF SAID YARN PACKAGE AT ALL TIMES DURING YARN REMOVAL THEREFROM, A SLIT LOCATED IN SAID RETARDING STRIP EXTENDING SUBSTANTIALLY PARALLEL TO THE AXIS OF SAID YARN PACKAGE AND COMPLETELY ACROSS SAID RETARDING STRIP, A U-SHAPED FASTENING PIN FOR SECURING THE ENDS OF SAID RETARDING STRIP ON EACH SIDE OF SAID SLIT, THE CLOSED END OF SAID U-SHAPED PIN BEING LOCATED ADJACENT THE BASE OF SAID PEG, A CLOSING STRIP OF MATERIAL SECURED ALONG ONE EDGE TO THE INNER FACE OF SAID RETARDING STRIP AND LOCATED COEXTENSIVE WITH SAID SLIT, THE OTHER EDGE OF SAID CLOSING STRIP OVERLYING SAID SLIT TO SHUT OFF COMMUNICATION OF SAID SLIT WITH THE SURFACE OF SAID YARN PACKAGE, AND A PLURALITY OF WEIGHTS SECURED AT CIRCUMFERENTIAL INTERVALS TO THE OUTER FACE OF SAID RETARDING STRIP. 